The Nimbus controller is $49 and is the one shown on the Apple website
Geometry Wars cost $10. Its doing great. So games that you have to pay up front can be successful on iOS/AppleTV. Look at Minecraft also. Bottom line is those games need to be WORTH $10.
There are tons of resources on the web to read about a game BEFORE you buy it. Giving free demo's is dumb. Just research before you decide to buy a game.